Lifelong social connections slow biological aging process
Researchers have found that sustained social bonds throughout life can slow cellular aging and reduce inflammation. The study, based on data from over 2,100 adults, shows that cumulative social advantages lead to younger biological profiles. This effect stems from consistent relationships rather than isolated interactions.
A new study published in the October 2025 issue of Brain, Behavior, and Immunity -- Health reveals how lifelong social support influences biological aging. Led by Anthony Ong, a psychology professor at Cornell University, the research analyzed data from more than 2,100 participants in the Midlife in the United States (MIDUS) study. It focused on "cumulative social advantage," defined as the depth and breadth of social connections over a lifetime.
The team used DNA-based epigenetic clocks, including GrimAge and DunedinPACE, which predict morbidity and mortality by measuring DNA methylation patterns. Participants with stronger, sustained social networks exhibited slower epigenetic aging and lower chronic inflammation. Higher social advantage correlated with reduced levels of interleukin-6, a pro-inflammatory molecule linked to heart disease, diabetes, and neurodegeneration. However, no significant links were found with short-term stress markers like cortisol or catecholamines.
Ong explained the four key areas assessed: warmth and support from parents in childhood, community and neighborhood connections, involvement in religious or faith-based groups, and ongoing emotional support from friends and family. "Cumulative social advantage is really about the depth and breadth of your social connections over a lifetime," Ong said.
Unlike prior research examining isolated factors like marriage or friend count, this study treated social advantage as a multidimensional construct that builds over time. "What's striking is the cumulative effect -- these social resources build on each other over time," Ong noted. "It's not just about having friends today; it's about how your social connections have grown and deepened throughout your life."
The findings underscore that consistent social ties across decades matter for health. Ong likened them to a retirement account: "The earlier you start investing and the more consistently you contribute, the greater your returns. Our study shows those returns aren't just emotional; they're biological. People with richer, more sustained social connections literally age more slowly at the cellular level. Aging well means both staying healthy and staying connected -- they're inseparable."